Fix to Hydrofill ATO or Which controller?

[itz frank]

I have a system that came with a hydrofill ato controller and pump system. The controller no longer works as one of the sensors always shows touching water.

So, can I fix this issue? There is no algae on the sensors and both have been cleaned. One works and one doesn't.

If not, what controller should I be looking at? I've googled JBJ and a few others but the negative reviews shy me away.